In a small bowl, combine soy, garlic, ginger, sugar, lemon juice, oil, onion, and pepper.
Place steak in a close-fitting baking dish; pour soy mixture over steak.
Cover and refrigerate for 6 hours or until next day, turning steak occasionally.
Remove steak from marinade and drain briefly, reserving marinade.
Place steak on a rack in a broiler pan
Broil about 3 inches below heat for 3 to 4 minutes on each side for rare or until done to your liking when slashed.
Meanwhile, heat reserved marinade in a small pan over medium heat until bubbly; pour into a small serving bowl.
Transfer meat to a carving board and cut across the grain into thin slanting slices.
Pass marinade at the table.